pub struct Notification {
        pub color: Color,
        pub message: String,
        pub message_format: MessageFormat,
    }
    #[repr(C)]
    pub struct CNotification {
        pub color: <Color as CRepr>::Output,
        pub message: <String as CRepr>::Output,
        pub message_format: <MessageFormat as CRepr>::Output,
    }
    impl CRepr for Notification {
        type Output = CNotification;
        fn to_c_repr(&self) -> Self::Output {
            CNotification{color: self.color.to_c_repr(),
                          message: self.message.to_c_repr(),
                          message_format: self.message_format.to_c_repr(),}
        }
    }
}